The original tests on this subject were run many years ago with the introduction of the pie crimp hull. The result was as Rocketman has already stated that virtually all factory loaded pie/fold crimp shells were/are longer than the short chambered guns, "Including Those Certified for use in Those Guns". These tests were all run with paper hulls & card & felt wadding. Bell just re-invented the wheel, it had all been established beginning in the late 1930's & completed immediately following WWII, by the end of the 1940's.
As to the length of the shell in relation to the chamber proper use of a shell longer than the chamber dictates a shell having a pie crimp & a "Loaded Length" very close to a roll crimp hull of same length as chamber. It is decidedly un-wise to fire roll crimp shells in a chamber shorter than the shell, especially if the shell is long enough the end of the loaded shell will be forced into the cone Prior to Firing.
PS; If you want a book which thoroughly discusses this along with about anything else you want to know concerning a shotgun get "The Modern Shotgun" by Burrard
Last edited by 2-piper; 08/22/13 03:57 PM. Reason: added PS
